Anthrax treatment developed by HGS headed for approval

FDA panel OKs therapy; agency scheduled to vote in December

Centers for Disease Control and Prevention
Bacillus anthracis bacteria spores are shown. A treatment for inhaled anthrax developed by Human Genome Sciences is on track for regulatory approval next month.

This story was updated on Nov. 9, 2012.

GlaxoSmithKline, the new owner of Rockville's Human Genome Sciences, cleared a significant regulatory hurdle last week when a Food and Drug Administration advisory panel overwhelmingly recommended that its anthrax treatment be approved.

Under a federal contract, HGS began work on raxibacumab, which it brands ABthrax, shortly after the anthrax attacks in September 2001 that infected 11 people, killing five of them.

Even though it has not been approved by the FDA, the company has sold ABthrax to the federal government's Strategic National Stockpile for emergency use for years; through 2011, its sales had generated $280 million in revenues for HGS, according to its most recent annual report. Under the Project BioShield Act of 2004, the federal government may purchase products such as ABthrax that have not received FDA approval. HGS stands to receive about $20 million from the government if raxibacumab is licensed by the FDA.

In 2009, the advisory panel said it needed more trial data before it could recommend approval of the monoclonal antibody treatment. In July, HGS resubmitted its application to the FDA for approval.

On Nov. 2, the FDA's Anti-Infective Drugs Advisory Committee, satisfied with the company's new trial data, reversed its 2009 stand and voted 16 to 1, with one abstention, to recommend approval of injected raxibacumab to treat inhalational anthrax. The FDA is scheduled to decide whether to OK the treatment on Dec. 15.

The agency is not required to follow its advisory committees’ recommendations, but it usually does.

HGS has tested raxibacumab on rabbits and monkeys, because under the FDA's so-called "animal rule" it would be unethical to test it on human subjects. Under that rule, demonstrating an experimental treatment's safety and efficacy on at least two different animal species is sufficient to help it pass regulatory muster. The treatment is manufactured at the company’s small-scale plant in Rockville, according to company information.

FDA approval of raxibacumab won’t necessarily mean more production or more employees at the Rockville plant, though production would continue there, GlaxoSmithKline spokeswoman Holly V. Russell said in an email, citing confidentiality under the company’s 2012 tender to the Department of Health and Human Services’ Biomedical Advanced Research and Development Authority’s solicitation.

ABthrax differs from other treatments in that it targets the toxins produced by the anthrax bacterium in the body, rather than the bacterium itself. Currently, the antibiotics known as Cipro and Levaquin are most often prescribed for inhalation anthrax; they can kill the bacterium, but are not effective against the lethal toxins the bacterium produces.

“Anthrax has been identified by the U.S. Government as a serious potential threat and there is a need for new treatment options in the event of an anthrax attack in the U.S.," Zhi Hong, senior vice president and head of infectious diseases at GlaxoSmithKline, said in a statement last week. "The development of raxibacumab reflects a collaboration of industry and government in response to this public health need, and we are pleased with the outcome of today’s meeting which represents years of dedication to this project by Human Genome Sciences.”

GlaxoSmithKline of London acquired HGS in July for $3.6 billion. Last month, it notified state officials of its plans to lay off 97 HGS workers. That followed notification in August of plans to lay off 114 employees. As of Feb. 1, the company had about 1,100 full-time employees, having laid off about 100 the previous month, according to a regulatory filing.

Russell declined to say how many employees are now at the former HGS location.

“The integration with HGS is ongoing,” she said. “We are maintaining manufacturing operations but cannot provide further detail.”

In other Maryland bioscience industry news:

Northwest Biotherapeutics has launched a collaboration with a British cancer center to study its experimental vaccine against colon cancer.

The Bethesda biotech already is conducting phase 3 trials of its DCVax for brain cancer. The new program with Sarah Cannon Research U.K. and the Leaders in Oncology Care of London will study its DCVax-Direct in a phase 1-2 clinical trial for metastatic colon cancer.

Sarah Cannon Research U.K. is the British arm of the Sarah Cannon Research Institute of Nashville, Tenn., which focuses on development cancer therapies and has a network of more than 700 physicians in the U.S. and U.K.

Northwest's treatment is designed to treat inoperable cancer in different parts of the body through a direct injection in the tumor, according to company information.

"Partnering with major institutions such as Sarah Cannon and [Leaders in Oncology Care] will enable us to benefit from their extensive oncology experience and broad reach, and will help accelerate our clinical trials with DCVax-Direct ," CEO Linda Powers said in a statement.

Among both sexes, cancer of the colon and rectum is second-leading cause of cancer deaths, after lung cancer, killing 20.2 per 100,000 American men and 14.1 per 100,000 American women annually, according to data from the National Cancer Institute. Individually, prostate and breast cancer each have higher mortality rates among men, 23.6 per 100,000, and women, 23.0 per 100,000, respectively.

Lung cancer, on the other hand, kills 65.7 per 100,000 men and 39.6 per 100,000 women.

Northwest has been OK'd by the FDA to hold a 36-patient phase 1-2 trial in any solid tumor cancers. The primary endpoint will be a measure of tumor response — regression — in patients' existing, established tumors. Under the new partnership, the company will seek regulatory approval of the trial in the U.K.

"We are excited to collaborate on this program with Northwest Bio," Hendrik-Tobias Arkenau, medical director of Sarah Cannon Research U.K., said in the statement. "There is an urgent need for better treatments for colon and other cancers. We believe that innovative immune therapies such as DCVax may offer significant improvements in cancer treatment and outcomes."

DCVax-Direct comprises the patient's own dendritic cells, which are the master cells of the immune system. They are activated in a proprietary way and directly injected into the patient's tumors, where they pick up the tumor biomarkers and mobilize the immune system to attack any tumors that have those biomarkers, according to Northwest information.

In animal studies, not only did injected tumors shrink, other tumors in the body did, too, indicating a systemic immune response. When the treated animals were later injected with cancer cells, they did not redevelop the cancer, which indicates immune memory.

DioGenix reported that its experimental test to diagnose multiple sclerosis was more specific in a clinical study than the current conventional test.

The Gaithersburg company’s lead product, MS Precise, analyzes cerebrospinal fluid in patients suspected of having multiple sclerosis. The recent study tested the product on both patients and healthy subjects in two cohorts of 40 to 45 patients each.

"The results of our most recent study continue to support our belief that MS Precise will be an important new tool in the management of patients suffering with MS. We have clearly demonstrated, in a series of clinical studies, the power of MS Precise to accurately identify patients in the early stages of neurodegenerative disease," CEO Larry Tiffany said in a statement. "We believe our deep sequencing approach has the potential to not only diagnose and classify patients with MS but eventually other immune-mediated neurological diseases as well."

DioGenix has started enrolling about 150 subjects in a new multisite clinical trial to further validate the results. The trial is designed to analyze subjects as they typically present to a neurologist and are being evaluated for a diagnosis of multiple sclerosis or other neurological disease, according to the company’s statement.

The test uses genetic sequencing to measure DNA mutations in cells isolated from cerebrospinal fluid. The body’s immune system, in response to a perceived challenge, generates these mutations.

DioGenix also reported that under a new alliance with Fast Forward, a subsidiary of the National Multiple Sclerosis Society, Fast Forward will provide up to $500,000 to support the company’s clinical trials.

According to the National Multiple Sclerosis Society, at least 400,000 Americans have the disease, and every hour someone is newly diagnosed.

The FDA has approved the use of Cytomedix’s system for processing small blood samples or mixtures of blood and bone marrow aspirate for use in bone-grafting applications, such as spinal fusion.

The Gaithersburg biotech’s system produces platelet-rich plasma, which can be mixed with bone graft material for such uses.

“We are pleased to reach this important regulatory milestone that will broaden utilization of the Angel cPRP System in a range of orthopedic procedures,” CEO Martin Rosendale said in a statement. “This is a significant market opportunity for Cytomedix as Angel cPRP will be positioned as a ‘best in class’ device that offers important competitive advantages including high platelet concentration capacity, efficient reduction of inflammatory cells, and an automated, closed system for all surgical settings.”

The system works better than others because it is faster, has high platelet yields and significantly reduces pro-inflammatory cells, Cytomedix said.

About 400,000 spinal fusion procedures are performed each year in the U.S., according to the company. The associated biologics market is about $700 million annually.

Supernus Pharmaceuticals reported winning two U.S. patents for its Trokendi XR, its once-daily extended-release topiramate product to treat epilepsy.

"This is a very important development for us as we continue to build intellectual property protection for our products. Each of our epilepsy products, Trokendi XR and Oxtellar XR, is now covered by two issued U.S. patents," Jack A. Khattar, CEO of the Rockville biotech, said in a statement.

RegeneRx Biopharmaceuticals has won a U.S. patent allowance for use of its thymosin beta 4 compound to treat patients with glaucoma and high intraocular pressure.

The patent will expire in 2026, according to a statement from the Rockville biotech.